Office chair



FIG. 1 is a front perspective view of an office chair showing my design;

FIG. 2 is a left side view;

FIG. 3 is a front elevational view;

FIG. 4 is a top view;

FIG. 5 is a rear elevational view; and

FIG. 6 is a right side view.

The ornamental design for an office chair, as shown and described.